Soffit — What It Is, Where Used, and Replacement Guide

A soffit is the finished underside surface of an overhang, usually at a roof eave, that covers framing and can support ventilation openings.

What It Is

On most houses, the soffit closes in the underside of the roof overhang between the wall and the fascia. It gives the eave a finished look, protects rafters from weather and pests, and often carries intake vents for the attic.

Interior bulkheads and porch ceilings can also be called soffits, but in residential exterior work the term usually means the underside of the eave.

Types

Common soffit materials include vented or solid vinyl panels, aluminum panels, fiber cement, wood boards, and exterior-rated plywood. The right type depends on the look of the house, exposure to moisture, and whether the attic needs intake ventilation at that location.

Where It Is Used

Soffits are used under roof eaves, porch overhangs, carports, and other exterior projections. They are also used below boxed-in beams or duct chases indoors, though those interior soffits serve a different purpose than roof-edge soffits.

How to Identify One

Look up at the underside of the roof overhang where the wall meets the roof edge. A soffit is the flat or sloped finished surface beneath that overhang, often bordered by siding on one side and fascia on the other.

Replacement

Replacement is needed when soffit panels sag, rot, rust, crack, or show pest entry points. Matching the material, venting pattern, and panel dimensions matters because the soffit works with fascia, gutters, and attic ventilation.